package org.bouncycastle.jce.provider;

import java.security.interfaces.RSAPrivateCrtKey;
import java.security.interfaces.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;

import org.bouncycastle.asn1.DERObjectIdentifier;
import org.bouncycastle.asn1.pkcs.PKCSObjectIdentifiers;
import org.bouncycastle.asn1.x509.X509ObjectIdentifiers;
import org.bouncycastle.crypto.params.RSAKeyParameters;
import org.bouncycastle.crypto.params.RSAPrivateCrtKeyParameters;

/**
 * utility class for converting java.security RSA objects into their
 * org.bouncycastle.crypto counterparts.
 */
class RSAUtil {
    static boolean isRsaOid(DERObjectIdentifier algOid) {
        return algOid.equals(PKCSObjectIdentifiers.rsaEncryption)
                || algOid.equals(X509ObjectIdentifiers.id_ea_rsa)
                || algOid.equals(PKCSObjectIdentifiers.id_RSASSA_PSS)
                || algOid.equals(PKCSObjectIdentifiers.id_RSAES_OAEP);
    }

    static RSAKeyParameters generatePublicKeyParameter(RSAPublicKey key) {
        return new RSAKeyParameters(false, key.getModulus(),
                key.getPublicExponent());

    }

    static RSAKeyParameters generatePrivateKeyParameter(RSAPrivateKey key) {
        if (key instanceof RSAPrivateCrtKey) {
            RSAPrivateCrtKey k = (RSAPrivateCrtKey) key;

            return new RSAPrivateCrtKeyParameters(k.getModulus(),
                    k.getPublicExponent(), k.getPrivateExponent(),
                    k.getPrimeP(), k.getPrimeQ(), k.getPrimeExponentP(),
                    k.getPrimeExponentQ(), k.getCrtCoefficient());
        } else {
            RSAPrivateKey k = key;

            return new RSAKeyParameters(true, k.getModulus(),
                    k.getPrivateExponent());
        }
    }
}
